Hydraulic liners are used to restrict hazardous leachates such as acid mine drainage (AMD) from entering the hydrogeological system. In this study, we hypothesized that: (1) a compacted mix ratio of natural clay and coal fly ash with a hydraulic conductivity of at most 1 × 10 ms can be achieved, and (2) mixing clay and coal fly ash in the right proportion can result in increased contaminant removal efficiency of a liner system. The effects of adding coal fly ash to clay on the mechanical behavior, contaminant removal efficiency, and saturated hydraulic conductivity of the liner were investigated. All clay:coal fly ash specimen liners with less than 30% coal fly ash had significantly (p < 0.05) lower cohesion stress values, and were discarded without further tests. Saturated hydraulic conductivity values showed no significant effect (p > 0.05) on the results of clay:coal fly ash (7:3) specimen liners and compacted clay liner. The clay:coal fly ash mix ratios of 8:2 and 7:3 significantly (p < 0.05) reduced the leachate concentration of Cu, Ni, and Mn. The pH of AMD increased from an average of 2.14 to 6.80 after permeating through a compacted specimen of mix ratio 7:3. Overall, the 7:3 clay to coal fly ash liner showed superior pollutant removal capacity and its mechanical and hydraulic properties were comparable to compacted clay liners. This laboratory scale investigation emphasizes potential limitations with column scale evaluation of liners and provides new information on the application of dual hydraulic reactive liners for engineered hazardous waste disposal systems.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1007/s00128-023-03743-3 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Waste marble sludge and calcined clay brick powders in conventional cement farina production for cleaner built environment.
Sci Rep
January 2025
Center for Global Health Research, Saveetha Institute of Medical and Technical Sciences, Saveetha University, Chennai, India.
In the manufacturing of some sectors, such as marble and brick, certain byproducts, such as sludge, powder, and pieces containing valuable chemical compounds, emerge. Some concrete plants utilize these byproducts as mineralogical additives in Turkey. The objective of the experimental study is to ascertain whether the incorporation of waste from the marble and brick industries, in powder form, into cement manufacturing as a mineralogical additive or substitute is a viable option.
View Article and Find Full Text PDFSolidified lake sediment with industrial waste and construction waste used as barrier cover material: mechanical strength, water resistance performance, and microscopic analysis.
Environ Technol
January 2025
School of Civil Engineering and Architecture, Wuhan Polytechnic University, Wuhan, People's Republic of China.
This study introduces a novel landfill cover material, employing lake sediment as a substrate, stabilised with fly ash, slag, desulfurisation gypsum and construction waste. The mechanical properties, including shear strength parameters, unconfined compressive strength, hydraulic conductivity, volumetric shrinkage, and water content, of the solidified sludge were evaluated. The microscopic mechanism of the solidified sludge were investigated through XRD, FTIR, and SEM-EDS techniques.
View Article and Find Full Text PDFDeamination mechanism of modified magnesium slag using wet aging and its performance evolution as backfill material.
J Environ Manage
January 2025
School of Business, Xi'an University of Finance and Economics, Xi'an, 710100, China.
The purpose of this study is to solve the problem of ammonia (NH) release when modified magnesium slag (MMS) is used as coal mine backfill cementitious material, and to explore its chemical mechanism and put forward effective solutions. Uniaxial compressive strengths (UCS) hydration kinetics, scanning electron microscope (SEM), and thermogravimetric analysis-derivative thermogravimetry (TG-DTG), X-ray diffractometer (XRD) and other testing methods were used to study the evolution of the properties of MMS-based backfill material, which provided a scientific basis for the safe utilization of MMS. First, the chemical mechanism underlying the release of NH from MMS was identified, and it was confirmed that MgN and LiN are the main nitrogen sources.
View Article and Find Full Text PDFLead/cadmium impacts on zeolite-tobermorite: Nutrient release and sediment stability.
Environ Pollut
January 2025
Department of Mineral Processing Engineering, Taiyuan University of Technology, Taiyuan, 030024, China.
To realize the comprehensive utilization of large amounts of high-ash coal slime and comprehensively understand the excellent performance of nutrient release and lead and cadmium adsorption of high-ash coal slime silicon composite materials, green and safe mild hydrothermal conditions (200 °C) were used to prepare the rich-rich coal slime. Zeolite/tobermorite composites (Z-TOBs) were used in this study. Batch adsorption tests and repeated extraction tests were used to determine whether silicon, potassium, and calcium nutrients of Z-TOBs have sustained release properties and are affected by pH.
View Article and Find Full Text PDFUnderestimated industrial ammonia emission in China uncovered by material flow analysis.
Environ Pollut
January 2025
State Key Laboratory of Pollution Control and Resources Reuse, School of Environment, Nanjing University, Nanjing, 210023, China; Collaborative Innovation Center of Atmospheric Environment and Equipment Technology, Nanjing University of Information Science & Technology, Nanjing, 210044, China. Electronic address:
Ammonia (NH) is crucial in fine particulate matter (PM) formation, but past estimations on industrial NH emissions remain highly uncertain. In this study, the flow of NH within air pollution control devices (APCDs) were investigated basing on material flow analysis with in-situ measurements of NH concentrations at the inlets and outlets of each APCD. Then, by combing emission factors updated with recent in-situ measurements and provincial-level activity data from statistical yearbooks and associated reports, NH emissions from various industrial sources, as well as their spatial distribution across China in 2020, were evaluated.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!